Methods, systems, and computer-readable storage media for receiving, from a first component and by a second component in a cloud platform, a call, a token, and a first client certificate, determining, by the second component, a first client identifier associated with the first component, and determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response: executing functionality responsive to the call.
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1. A computer-implemented method for secure access token forwarding between components in cloud platforms, the method being executed by one or more processors and comprising:
receiving, from a first component and by a second component in a cloud platform, a first call, a token, and a first client certificate; wherein the token provided to the first component in response to a request from the first component to a central identity and authentication service (IAS) of the cloud platform, and the first client certificate is provided during execution of a process to generate the token;
determining, by the second component, a first client identifier associated with the first component;
determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response:
executing functionality responsive to the first call;
receiving, from a third component and by the second component, a second call, the token, and a second client certificate;
determining, by the second component, a second client identifier associated with the third component; and
determining, by the second component, that the second client identifier is absent from the manifest of the token, and in response:
transmitting an error to the third component.
5. A non-transitory computer-readable storage medium coupled to one or more processors and having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations for secure access token forwarding between components in cloud platforms, the operations comprising:
receiving, from a first component and by a second component in a cloud platform, a first call, a token, and a first client certificate; wherein the token provided to the first component in response to a request from the first component to a central identity and authentication service (IAS) of the cloud platform, and the first client certificate is provided during execution of a process to generate the token;
determining, by the second component, a first client identifier associated with the first component;
determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response:
executing functionality responsive to the first call;
receiving, from a third component and by the second component, a second call, the token, and a second client certificate;
determining, by the second component, a second client identifier associated with the third component; and
determining, by the second component, that the second client identifier is absent from the manifest of the token, and in response:
transmitting an error to the third component.
9. A system, comprising:
a computing device; and
a computer-readable storage device coupled to the computing device and having instructions stored thereon which, when executed by the computing device, cause the computing device to perform operations for natural language explanations for secure access token forwarding between components in cloud platforms, the operations comprising:
receiving, from a first component and by a second component in a cloud platform, a first call, a token, and a first client certificate; wherein the token provided to the first component in response to a request from the first component to a central identity and authentication service (IAS) of the cloud platform, and the first client certificate is provided during execution of a process to generate the token;
determining, by the second component, a first client identifier associated with the first component;
determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response:
executing functionality responsive to the first call;
receiving, from a third component and by the second component, a second call, the token, and a second client certificate;
determining, by the second component, a second client identifier associated with the third component; and
determining, by the second component, that the second client identifier is absent from the manifest of the token, and in response:
transmitting an error to the third component.
2. The method of
3. The method of
4. The method of
6. The computer-readable storage medium of
7. The computer-readable storage medium of
8. The computer-readable storage medium of
10. The system of
11. The system of
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Cloud computing can be described as Internet-based computing that provides shared computer processing resources, and data to computers and other devices on demand. Users can establish respective sessions, during which processing resources, and bandwidth are consumed. During a session, for example, a user is provided on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage, applications, and services). The computing resources can be provisioned and released (e.g., scaled) to meet user demand.
A common architecture in cloud platforms includes microservices (also referred to as services), which have gained popularity in service-oriented architectures (SOAs). In the microservice architecture, applications are composed of multiple, independent services, and are deployed in standalone containers with a well-defined interfaces. The services are deployed and managed by a cloud platform, and run on top of a cloud infrastructure. In microservice architectures the primary attention is on communication between services, especially on secure communication.
Security here has several aspects, one aspect including authentication. There are multiple dimensions to authentication. Examples dimensions include authenticating components calling a service (e.g., a service another service, an application calling a service), and authenticating a user on whose behalf the call is made. In some instances, both dimensions are addressed in a single token (e.g., such as an open authentication (OAuth) access token), which authenticates both the calling component and the user. In such instances, a different token is needed for each communication leg in a chain of service calls, because the calling component changes with each call. This requires a token exchange, which is often recognized as overhead and undesired complexity. However, this has been a traditional approach in an effort to avoid compromising security. While alternative security approaches have been introduced, such approaches introduce their own security issues.
Implementations of the present disclosure are directed to secure token forwarding that addresses security challenges in microservice architectures. More particularly, implementations of the present disclosure restrict arbitrary forwarding of tokens using a manifest of allowed communication routes and enabling each service to determine whether a caller is allowed to call the service.
In some implementations, actions include receiving, from a first component and by a second component in a cloud platform, a first call, a token, and a first client certificate, determining, by the second component, a first client identifier associated with the first component, and determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response: executing functionality responsive to the first call. Other implementations of this aspect include corresponding systems, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.
These and other implementations can each optionally include one or more of the following features: executing functionality responsive to the first call at least partially includes transmitting, from the second component and to a third component, a second call with the token; the token is received by the first component from a third component; actions further include receiving, from a third component and by the second component, a second call, the token, and a second client certificate, determining, by the second component, a second client identifier associated with the third component, and determining, by the second component, that the second client identifier is absent from the manifest of the token, and in response: transmitting an error to the third component; the token provided to the first component in response to a request from the first component to a central identity and authentication service (IAS) of the cloud platform, the request including the first client certificate; the first client certificate is provided during execution of a process to generate the token; the token includes an open authentication (OAuth) client having an audience field populated with the manifest; and the first client certificate includes a X.509 client certificate.
The present disclosure also provides a computer-readable storage medium coupled to one or more processors and having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations in accordance with implementations of the methods provided herein.
The present disclosure further provides a system for implementing the methods provided herein. The system includes one or more processors, and a computer-readable storage medium coupled to the one or more processors having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations in accordance with implementations of the methods provided herein.
It is appreciated that methods in accordance with the present disclosure can include any combination of the aspects and features described herein. That is, methods in accordance with the present disclosure are not limited to the combinations of aspects and features specifically described herein, but also include any combination of the aspects and features provided.
The details of one or more implementations of the present disclosure are set forth in the accompanying drawings and the description below. Other features and advantages of the present disclosure will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
Implementations of the present disclosure are directed to secure token forwarding that addresses security challenges in microservice architectures. More particularly, implementations of the present disclosure restrict arbitrary forwarding of tokens using a manifest of allowed communication routes and enabling each service to determine whether a caller is allowed to call the service. Implementations can include actions of receiving, from a first component and by a second component in a cloud platform, a call, a token, and a first client certificate, determining, by the second component, a first client identifier associated with the first component, and determining, by the second component, that the first client identifier is included in a manifest of the token, the manifest defining at least a portion of a communication path between components within the cloud platform, and in response: executing functionality responsive to the call.
To provide further context for implementations of the present disclosure, and as introduced above, cloud computing can be described as Internet-based computing that provides shared computer processing resources, and data to computers and other devices on demand. Users can establish respective sessions, during which processing resources, and bandwidth are consumed. During a session, for example, a user is provided on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage, applications, and services). The computing resources can be provisioned and released (e.g., scaled) to meet user demand.
A common architecture in cloud platforms includes microservices (also referred to as services), which have gained popularity in service-oriented architectures (SOAs). In the microservice architecture, applications are composed of multiple, independent services, and are deployed in standalone containers with a well-defined interfaces. The services are deployed and managed by a cloud platform, and run on top of a cloud infrastructure.
As also introduced above, in microservice architectures the primary attention is on communication between services, especially on secure communication. Security here has several aspects, one aspect including authentication. There are multiple dimensions to authentication. Examples dimensions include authenticating components calling a service (e.g., a service another service, an application calling a service), and authenticating a user on whose behalf the call is made. In some instances, both dimensions are addressed in a single token (e.g., such as an open authentication (OAuth) access token), which authenticates both the calling component and the user. In such instances, a different token is needed for each communication leg in a chain of service calls, because the calling component changes with each call. This requires a token exchange, which is often recognized as overhead and undesired complexity. However, this has been a traditional approach in an effort to avoid compromising security.
As an alternative, the multiple authentication dimensions can be addressed with respective orthogonal security means. For example, if the calling component is authenticated using client certificates (e.g., X.509 client certificates used by SSL/TLS) and the token only identifies the user (e.g., OpenID Connect (OIDC) tokens), then one originally issued token can be forwarded and can be combined with each component's private client certificate. While this approach successfully avoids the need for exchanging tokens, it creates new security challenges. A first security challenge includes how to restrict which components are allowed to forward an identity token along a defined communication route to specific services. A second security challenge includes how to enforce these restrictions in order to prevent malicious components from impersonating users at services that the malicious components should not get access to.
As an example of these threats, an attacker could deploy two applications to a cloud platform marketplace. A first application can be apparently innocuous, as it does not request access to any services containing sensitive data. A second application can legitimately require access to a master data service that, for example, contains all of the employee data for a company (a so-called critical service). In this example, only the second application gets a client certificate that allows the second service to call the master data service, while the first application is not able to obtain its own client certificate. If a company subscribes to the first application and a user of the company logs on, the first application should not be able to use the identity token of the user to access the master data service. However, unless restricted otherwise, the first application could pass the identity token illicitly to the second application that does have a valid client certificate for accessing the master data service. Although the company did not subscribe to this second application, the second application could still use its client certificate to call the master data service with the identity token illicitly received from the first application and access data on behalf of the user that logged into the first application.
In an environment like a cloud platform where development partners, consultant companies, and even individual developers can offer applications in an open marketplace, attacks that are based on illicit token forwarding must be prevented by the cloud platform. More particularly, applications may only access data (e.g., customer data, employee data) as declared, so customers can judge which access they grant to which third party applications and rely on these restrictions to be enforced.
In view of the above context, implementations of the present disclosure provide secure token forwarding that addresses security challenges, such as the security challenges described herein. More particularly, implementations of the present disclosure restrict arbitrary forwarding of tokens using a manifest of allowed communication routes. In some implementations, the manifest is recorded in a field of an identity token (e.g., the audience (aud) field of an OIDC token). In some implementations, services are able to authenticate their callers and can verify that the caller is allowed to call the service according to the manifest.
In some examples, the client device 102 can communicate with the server system 104 over the network 106. In some examples, the client device 102 includes any appropriate type of computing device such as a desktop computer, a laptop computer, a handheld computer, a tablet computer, a personal digital assistant (PDA), a cellular telephone, a network appliance, a camera, a smart phone, an enhanced general packet radio service (EGPRS) mobile phone, a media player, a navigation device, an email device, a game console, or an appropriate combination of any two or more of these devices or other data processing devices. In some implementations, the network 106 can include a large computer network, such as a local area network (LAN), a wide area network (WAN), the Internet, a cellular network, a telephone network (e.g., PSTN) or an appropriate combination thereof connecting any number of communication devices, mobile computing devices, fixed computing devices and server systems.
In some implementations, the server system 104 includes at least one server and at least one data store. In the example of
In accordance with implementations of the present disclosure, and as noted above, the server system 104 can represent a cloud platform that hosts microservices (also referred to herein as services). For example, the server system 104 can host a service-based architecture that can process calls from an application based on the secure identity token forwarding of the present disclosure, described in further detail herein.
As introduced above, implementations of the present disclosure prevent arbitrary forwarding of tokens based on a manifest included with identity tokens (e.g., OIDC token), the manifest defining an allowed communication route for forwarding of the identity token. In some examples, the manifest is provided in a field of the identity token (e.g., and of an OIDC token). Further, a service receiving a call is able to authenticate the caller and verify that the caller is allowed to call the service according to the manifest.
In further detail, components that request access to call services declare these services as dependencies in a central identity and authentication service (IAS). The IAS can aggregate this information across all component-to-service relations to construct the complete communication routes from an application to all services used directly or indirectly by the application. Each service provides a client certificate to their calling components that uniquely identify individual legs of communication routes. More particularly, a client certificate uniquely identifies the component that sends the client certificate with a call. There may be different routes sharing common legs, so a component can always its same client certificate when calling a service along any route. This is true no matter in which context the call is made (i.e., from which application the call chain originated).
The client certificate can be used by a receiving component to authenticate the sending component using a public key infrastructure (PKI). An example client certificate includes the X.509 client certificate, which uses the X.509 PKI standard to verify that a public key belongs to a component. Authentication of the sending component by the receiving component is a known process using the PKI. Consequently, a detailed description of the authentication is foregone.
In accordance with implementations of the present disclosure, the IAS issues and signs identity tokens that include a manifest of allowed legs of the communication routes. When forwarded, called services verify that the direct caller (e.g., user, service) is authorized to act on behalf of the user stated in the identity token by cross-checking that the client certificate of the caller identifies a leg of the communication route listed in the manifest of the identity token.
In this manner, applications can request identity tokens that capture allowed communication routes. These identity tokens can only be forwarded to services along these routes, and no component can skip intermediate services, call back to components it was called from or pass the identity token to another component to use the identity token along communication routes outside of that defined in the identity token.
In constructing a communication route, the service manager (SM) 212 manages service instances that represent components in communication routes. These instances can be used to declare dependencies among components to the IAS 210, which enables the IAS 210 to construct the manifest of allowed communication routes. In
As described in further detail herein, getting or provisioning of a “service instance” of a service (e.g., such as the IAS) means, that the consumer of the service (e.g., the developer of the second service in the case of
In further detail, and with continued reference to
With particular reference to
The IAS 210 associates the identifier id19 to a client with the identifier client19. The client enables a component in possession of the client to fetch a token to get access to associated resources without demonstrating possession of the client itself. An example token includes the OIDC identity token (that can be used as an OAuth bearer token). It is contemplated, however, that implementations of the present disclosure can be realized with any appropriate token. The IAS 210 returns a client certificate 312 (e.g., X.509 certificate) and a client 314 to the service instance 206. The client certificate 312 includes the identifier client19. The client 314 includes the identifier populated with client19 and an audience field (aud) populated with the identifier client19. Because this is the first service created, the IAS 210 has no route to store from client19 to any other client. Consequently, the IAS 210 stores the reference client19 →n/a.
With the setup established as depicted in
Referring now to
In response, to receiving the request 320, the service 206 sends a request 322 to the IAS 210 to create a clone of the client with identifier client19 (e.g., the authentication client 314 of
In response to receiving the request 322, the IAS 210 associates identifier id38 to a client with identifier client38. The IAS 210 returns a client certificate 324 that includes the identifier client38 and an client 326 with identifier client38 to the service 206, which returns both to the service 204. The client 326 is a clone of the client 314, but has aud populated with identifier client38. Because the original client19 has no route stored from client19 to any other client, no other client identifier is added to aud.
With the setup established as depicted in
Referring now to
In response to the request 330, the IAS 210 associates identifier id23 to a client with identifier client23 and also stores the route from client23 to client38 associated with id38. The IAS 210 returns a client certificate 332 and a client 334 to the first service 204. The client certificate 332 includes identifier client23 to the service instance id23 and the client 334 includes identifier client23 and aud populated with identifiers client23 and client38, because it has stored a route from client23 to client38. Consequently, the aud of client 334 expresses the allowed use of the second service by the first service.
With this setup established as depicted in
Referring now to
In response to the request 340, the service 204 sends a request 342 to the IAS 210 to create a clone of its own client with identifier client23 (i.e., the client 334) for the service instance with identifier id49. The service 204 authenticates the request by presenting the client certificate 332 (with identifier client23). In response, the IAS 210 associates identifier id49 to a client with identifier client49. The IAS 210 returns a client certificate 344 that includes the identifier client49 and a client 346 with identifier client49 to the service 204, which returns both to the application 202. The client 346 is a clone of the client 334, but has aud populated with identifiers client49 and client38, because the original client23 has a route stored from client23 to client38.
With this setup established as depicted in
Referring now to
In response to the request 350, the IAS 210 associates the identifier id84 to a client with identifier client84 and also stores the route from client84 to client49 associated with id49. The IAS 210 returns a client certificate 352 and a client 354. The client 354 includes aud populated with identifiers client84, client49 and client38, because the IAS 210 has stored a route from client84 to client 49 and a route from client49 to client38. This expresses the allowed use of the service 204 by the application 202 and use of the service 206 by the service 204.
With this setup established, the client 354 (client84) can be used to get a token from the IAS 210 that includes client84, client49 and client38 in aud. With this token and the client certificate with identifier client84 (i.e., the client certificate 352), the service 204 can be called and can verify that the call is valid, because the identifier from the client certificate is in aud of the token. The service 204 can use the same token to call the service 206 with the client certificate that the service 204 received when creating its service instance of the second service 206 with the identifier client38 (i.e., the client certificate 324). The service instance 206 can verify that the call is valid, because the identifier from the client certificate is in the aud of the access token.
Accordingly, after the progression of
Referring again to
For example, the application 202 performs a redirect to the IAS 210, requesting that the IAS 210 logon the user. In response, the IAS 210 presents a UI for username and password, such that the user enters the credentials directly to the IAS 210. Example credentials can include a user identifier (user id) and password. In the example of
In response to receiving the authentication code, the application 202 sends a request 220 to the IAS 210 to request an access token for the user 215. The request 220 includes the authentication code (e.g., [client84, 0815)). The request 220 is sent with the client 354 (with identifier client84) and the client certificate 352 (with identifier client84). The IAS 210 returns an identity token 222 (e.g., OIDC token) for the user 215 with the user identifier and client84, client49 and client38 in aud (e.g., aud: client84, client49, client38).
With the identity token 222 and the client certificate 352 (with identifier client84), the application 202 can call the service instance 204. The service instance 204 can verify that the call is valid, because the identifier from the client certificate (i.e., client84) is in aud of the identity token 222. The service instance 204 can use the identity token 222 to call the service 206 with the client certificate 324 (with client38) that the service 204 received when creating its instance of service 206. The service instance 206 can verify that the call from the service instance 204 is valid, because the identifier from the client certificate 324 is in and of the identity token 222.
A request is received from a first component (402). For example, a second component receives the request from the first component, and the request includes a request to establish a communication path between the first component and the second component. In some examples, the request includes values for each of sub-account, name, instance identifier. For example, and as described above with reference to
A request is transmitted to an IAS (404). For example, in response to receiving the request from the first component, the second component transmits a request to the IAS for a clone of the client of the second component. In some examples, the request includes a client identifier of the second component and an instance identifier associated with the request from the first component. The request is transmitted with a client certificate of the second component. For example, and as described above with reference to
A client and a second client certificate are received (406). For example, the second component receives the client and the second client certificate from the IAS. In some examples, the client includes a manifest defining a path including the first component. In some examples, the second client certificate includes a client identifier associated with an instance requested by the first component. For example, and with reference to
The client and the second client certificate are transmitted to the first component (408). For example, the second component transmits the client and the second client certificate to the first component. With continued reference to
A call is received from a first component (502). For example, a second component receives the call from the first component. In some examples, the call includes a call for the second component to perform some functionality and provide a response back to the first component. For example, and with reference to
A client identifier is determined from the client certificate (504). For example, the second component reads the client identifier from the client certificate. A path is determined from a manifest of the token (506). For example, the second component reads the manifest (e.g., from aud) of the token. It is determined whether the client identifier is included in the path (508). If the client identifier is included in the path, the call is processed (510). For example, the second component performs functionality and provided some result. With reference to
Referring now to
The memory 620 stores information within the system 600. In some implementations, the memory 620 is a computer-readable medium. In some implementations, the memory 620 is a volatile memory unit. In some implementations, the memory 620 is a non-volatile memory unit. The storage device 630 is capable of providing mass storage for the system 600. In some implementations, the storage device 630 is a computer-readable medium. In some implementations, the storage device 630 may be a floppy disk device, a hard disk device, an optical disk device, or a tape device. The input/output device 640 provides input/output operations for the system 600. In some implementations, the input/output device 640 includes a keyboard and/or pointing device. In some implementations, the input/output device 640 includes a display unit for displaying graphical user interfaces.
The features described can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The apparatus can be implemented in a computer program product tangibly embodied in an information carrier (e.g., in a machine-readable storage device, for execution by a programmable processor), and method steps can be performed by a programmable processor executing a program of instructions to perform functions of the described implementations by operating on input data and generating output. The described features can be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. A computer program is a set of instructions that can be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.
Suitable processors for the execution of a program of instructions include, by way of example, both general and special purpose microprocessors, and the sole processor or one of multiple processors of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. Elements of a computer can include a processor for executing instructions and one or more memories for storing instructions and data. Generally, a computer can also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and optical disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, ASICs (application-specific integrated circuits).
To provide for interaction with a user, the features can be implemented on a computer having a display device such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor for displaying information to the user and a keyboard and a pointing device such as a mouse or a trackball by which the user can provide input to the computer.
The features can be implemented in a computer system that includes a back-end component, such as a data server, or that includes a middleware component, such as an application server or an Internet server, or that includes a front-end component, such as a client computer having a graphical user interface or an Internet browser, or any combination of them. The components of the system can be connected by any form or medium of digital data communication such as a communication network. Examples of communication networks include, for example, a LAN, a WAN, and the computers and networks forming the Internet.
The computer system can include clients and servers. A client and server are generally remote from each other and typically interact through a network, such as the described one. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
In addition, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.
A number of implementations of the present disclosure have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the present disclosure. Accordingly, other implementations are within the scope of the following claims.
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